Citrogramma wyatti, 2012

Mengual, Ximo, 2012, The flower fly genus Citrogramma Vockeroth (Diptera: Syrphidae): illustrated revision with descriptions of new species, Zoological Journal of the Linnean Society 164 (1), pp. 99-172 : 167-168

CITROGRAMMA WYATTI MENGUAL SP. NOV.

Description

Male: Head: Face with facial tubercle, gradually sloping dorsally, more abrupt ventrally, entirely yellow, yellow pilose; gena yellow with broad dark macula on genal groove, yellow pilose with brown hairs on dark area, white pollinose posteriorly; holoptic; lunule yellow; frontal triangle yellow with anteromedial orangish macula, broad (about 115°), black pilose ( Fig. 105 ); vertical triangle black, shorter than eye contiguity, black pilose; ocelli dark; antenna yellow, black pilose on scape and pedicel; basoflagellomere yellowish, dark dorsally; arista black; occiput black, golden pollinose, pale pilose on ventral half, yellow pilose on dorsal half with black hairs on dorsal quarter.

Thorax: Scutum black, black and yellow pilose dorsomedially, with lateral broad yellow vitta; postpronotum yellow; notopleuron yellow continuing until scutellum, notopleuron and supra-alar area densely yellow pilose laterally; postalar callus yellow, black pilose; scutellum yellow with medial broad black macula reaching anterior and posterior margins, black pilose, complete subscutellar fringe of black hairs. Pleuron mostly yellow, except posterior anepisternum dark brown on anterior half, katepisternum black with dorsal yellow macula, meron black, anterior anepimeron dark dorsally, katatergum dark posteriorly, entirely yellow pilose; metasternum pilose; calypter yellow, blackened dorsally with dark and yellow hairs on margin; plumula yellow; halter yellow; spiracular fringes yellow.

Wing: Wing membrane hyaline, stigma dark, entirely microtrichose. Alula microtrichose, broad, slightly broader than cell BM.

Legs: Coxa and trochanter yellow except mesocoxa and mesotrochanter dark; pro- and mesofemur yellow, brownish distally; pro- and mesotibia yellow; pro- and mesotarsus dark; metafemur yellow, black on distal half; metatibia and metatarsus black; black pilose except basal femur and coxa yellow pilose.

Abdomen: Figure 103 . Parallel-sided, dorsum mainly black, black pilose dorsally and laterally except tergum 1 yellow pilose laterally and tergum 2 yellow pilose laterally on anterobasal half; tergum 1 black, yellow laterally; tergum 2 black with two mesolateral round yellow maculae, laterally extending forward to anterolateral tergal margin (like ‘golf club’-shaped spots), yellow lateral margin on anterior third; tergum 3 with yellow fascia with anterior margin parallel to tergal margin and posterior margin slightly concave; tergum 4 black with straight yellow fascia parallel to tergal margin; tergum 5 black with two triangular yellow maculae; terga 2, 3, 4, and 5 with anterior narrow black fascia and posterior bright pollinose vitta; sterna yellowish, black and yellow pilose; male genitalia as in Figure 146 .

Female: Similar to male except for normal sexual dimorphism and as follows: frons yellow, orangish medially, with lateral black vitta on dorsal half forming a narrow vitta on anterior ocellus ( Fig. 106 ); lunule yellow; occiput yellow pilose on ventral two thirds, black pilose on dorsal third; notopleuron and supra-alar area densely yellow pilose ventrally, with little black hairs dorsally ( Fig. 106 ); abdominal tergum 2 with narrow yellow fascia laterally extending forward to anterolateral tergal margin; terga 3 and 4 black with narrow straight yellow fascia, about quarter of tergum length; tergum 5 with two triangular yellow maculae joined medially; terga 2, 3, 4, and 5 with posterior bright pollinose vitta on posterior margin ( Fig. 104 ).

Length (N = 2): Body, 8.9–9.4 (9.1) mm; wing, 8.0–8.6 (8.3) mm.

Geographical distribution: New Guinea. Etymology: The specific epithet honours Nigel Wyatt (Curator of Diptera, BMNH, London, UK ). This new species is dedicated to him for his kindness and help during my visit to the BMNH and as recognition of his review of Citrogramma ( Wyatt, 1991) , which was very useful during this revisionary work. Species epithet to be treated as a noun in apposition.

Differential diagnosis: Species with face yellow, posterior anepisternum partly black, scutellum yellow with a broad black triangular macula reaching anterior and posterior margins ( Figs 103, 104 ), pro- and mesofemur yellow and metafemur yellow on basal half, and gena entirely yellow. Very similar to C. currani but that species has no black macula on genal groove and its lunule is yellow.

Remarks: See comments on C. currani .

Holotype male deposited in the Bernice P. Bishop Museum (Honolulu, Hawaii, USA) and labelled: ‘NEW GUINEA: PAPUA/Owen Stanley Range/ Goilala: Loloipa/ XI–25–XII–10–1957 ’ ‘W.W. Brandt/ Collector/BISHOP’ ‘ HOLOTYPE / Citrogramma / wyatti /det. X. Mengual 20 10 ’ [red, second and third lines handwritten].

Type locality: Papua New Guinea: Owen Stanley Range , Central Province , Goilala District, Loloipa, 8°21′S, 146°59′E .

Material examined: Type material. Holotype, as above. Paratype. INDONESIA: West Papua, Heuvelbivak, 800 m, 7–15.xi.1909, Lorentz [1♀, ZMAN] .

Figures

Figures 100–111. 100, Citrogramma variscutatum, dorsal view of female abdomen. 101–102, Citrogramma currani: 101, dorsal view of male abdomen; 102, dorsal view of female abdomen. 103–106, Citrogramma wyatti: 103, dorsal view of male abdomen; 104, dorsal view of female abdomen; 105, anterodorsal view of male head; 106, dorsal view of female head. 107, Citrogramma fascipleurum, anterodorsal view of female head. 108–109, Citrogramma difficile: 108, frontal view of male head; 109, dorsal view of female head. 110, C. fascipleurum, lateral view of female pleuron and head. 111, C. difficile, dorsal view of head, scutum and scutellum.

Figures 145–150. Male genitalia. 145, Citrogramma matsumurai, left lateral view. 146, Citrogramma wyatti, left lateral view. 147–148, Citrogramma pennardsi: 147, left lateral view; 148, tergum 9 and surstyli, dorsal view. 149, Citrogramma robertsi, left lateral view. 150, Citrogramma quadratum, left lateral view.